Electronic commerce is an increasingly popular way of selling products and services, referred to herein collectively and interchangeably as “items,” to consumers. Activities of electronic commerce typically, but not exclusively, include browsing for items to purchase; comparing various aspects such as price, color, warranties, and the like of items for purchase; inspecting product details of an item; purchasing one or more items; and the like. The popularity of electronic commerce (sometimes referred to as “e-commerce”) has prompted more vendors to make their products and services available over electronic networks, such as the Internet, and computer users have correspondingly embraced electronic commerce as a legitimate shopping environment.
Both vendors and computer users benefit from electronic commerce in a variety of ways. For example, users do not have to travel to a number of vendor locales to purchase a given item. Rather, a user can now purchase a desired item from the convenience of his or her home. Further, users can quickly compare a wide variety of similar items and prices from a number of vendors in order to make an informed choice in their purchases rather than spending an entire afternoon comparison shopping. Vendors are benefited in that they can reach a much larger group of customers than those who reside in their geographic vicinity.
Items that are sold in e-commerce are often complementary to one another. For example, a digital camera may have a number of complementary accessories such as batteries, memory cards, and tripods. These complementary items may have a one-to-one or a one-to-many relationship with a base item of interest. In the camera example, the camera may only work with a particular tripod made by the same manufacturer (a one-to-one relationship), while the same camera may work with a wide variety of batteries or memory cards (a one-to-many relationship). While some of these complementary items may be desirable to a user purchasing the digital camera, the user may not know of these relationships or may not have the time to investigate them. Thus, it is desirable for users who interact with e-commerce vendors to be able locate these complementary items easily and for vendors to promote these complementary items to the users to in order to increase sales.